const app = new Vue({
    el:'#app',
    data:{
        books:[
            {
                id:1,
                name:'《算法导论》',
                data: '2006-9',
                price:85.00,
                count:1
            },
            {
                id:2,
                name:'《UNIX编程艺术》',
                data: '2006-2',
                price:59.00,
                count:1
            },
            {
                id:3,
                name:'《编程珠玑》',
                data: '2008-10',
                price:39.00,
                count:1
            },
            {
                id:4,
                name:'《代码大全》',
                data: '2006-3',
                price:128.00,
                count:1
            }
        ]
    },
    methods:{
        getPrice(price){
            return '¥'+price.toFixed(2)
        },
        decrement(index){
            console.log('decrement')
            this.books[index].count--
        },
        increment(index){
            console.log('increment')
            this.books[index].count++
        },
        remove(index){
            this.books.splice(index,1)
        }
    },
    filters:{
      showPrice(price){
          return '¥'+ price.toFixed(2)
      }
    },
    computed:{
        totalPrice(){
            let totalPrice = 0
            for (let i = 0;i < this.books.length;i++){
                totalPrice += this.books[i].price * this.books[i].count
            }
            return totalPrice
        }
    },
})